Buggy code:
public class Debug { public static final String STANDARD_CONFIGFILE = ".debug" ; public static final String STANDARD_LOGFILE = "log" ; public static final int STANDART_WARN_LEN = 2 ; public static final int STANDART_ERR_LEN = 20 ; public static final String RESET = "[0m" ; public static final String FBLACK = "[30m" ; public static final String FRED = "[31m" ; public static final String FGREEN = "[32m" ; public static final String FYELLOW = "[33m" ; public static final String FBLUE = "[34m" ; public static final String FPURPLE = "[35m" ; public static final String FCYAN = "[36m" ; public static final String FWHITE = "[37m" ; public static final String BBLACK = "[40m" ; public static final String BRED = "[41m" ; public static final String BGREEN = "[42m" ; public static final String BYELLOW = "[43m" ; public static final String BBLUE = "[44m" ; public static final String BPURPLE = "[45m" ; public static final String BCYAN = "[46m" ; public static final String BWHITE = "[47m" ; public static final String NOTE_COLOR = Debug . FYELLOW ; public static final String ONCE_COLOR = Debug . FYELLOW ; public static final String TIME_COLOR = Debug . FCYAN ; public static final String TEST_COLOR = Debug . FPURPLE ; public static final String WARN_COLOR = Debug . FRED ; public static final String ERROR_COLOR = Debug . FRED ; private static boolean WRITE_TO_SCREEN = false ; private static boolean WRITE_TO_LOGFILE = false ; private static int ERR_LEN = Debug . STANDART_ERR_LEN ; private static int WARN_LEN = Debug . STANDART_WARN_LEN ; public static enum Tags { NETWORK ( true ) , LOBBYMENUINFO ( true ) , EXTENDED_WARNINGS ( false ) ; private boolean active ; Tags ( boolean active ) { } public boolean isActive ( ) { } } private static LinkedList < String > logs = new LinkedList < String > ( ) ; private static long lastTime = 0 ; private Debug ( ) { } public static void init ( ) { } public static void note ( String string , Debug . Tags tag ) { } public static void note ( String string ) { } public static void once ( String string , Debug . Tags tag ) { } public static void once ( String string ) { } public static void testTrace ( String string ) { } public static void test ( String string ) { } public static void time ( String string , Debug . Tags tag ) { } public static void time ( String string ) { } public static void warnIf ( boolean b , String s , Debug . Tags tag ) { } public static void warnIf ( boolean b , String s ) { } public static void warn ( String string , Debug . Tags tag ) { } public static void warn ( String string ) { } private static void warn ( String string , StackTraceElement [ ] trace ) { } public static void error ( String string , Debug . Tags tag ) { } public static void error ( String string ) { } private static void error ( String string , StackTraceElement [ ] trace ) { } private static void colorLog ( String color , String string ) { } private static void colorLog ( String color , String string , boolean force ) { } public static boolean isLogged ( String string ) { } private static void log ( String string ) { } private static void log ( String string , boolean force ) { } private static void addLog ( String string ) { } private static void loadConfigFile ( ) { if ( new File ( Debug . STANDARD_CONFIGFILE ) . isFile ( ) ) { BufferedReader br = null ; try { br = new BufferedReader ( new FileReader ( Debug . STANDARD_CONFIGFILE ) ) ; StringBuilder sb = new StringBuilder ( ) ; String line ; while ( ( line = br . readLine ( ) ) != null ) { if ( line . equals ( "logfile=on" ) ) Debug . WRITE_TO_LOGFILE = true ; if ( line . equals ( "screen=on" ) ) Debug . WRITE_TO_SCREEN = true ; if ( line . startsWith ( "warnlen=" ) ) Debug . WARN_LEN = Integer . parseInt ( line . substring ( 8 ) ) ; if ( line . startsWith ( "errlen=" ) ) <START_BUG> Debug . ERR_LEN = Integer . parseInt ( line . substring ( 6 ) ) ; <END_BUG> } } catch ( Exception e ) { System . out . println ( ( ( "Debug.loadConfigFile():<seq2seq4repair_space>error<seq2seq4repair_space>loading<seq2seq4repair_space>config-file<seq2seq4repair_space>\"" + ( Debug . STANDARD_CONFIGFILE ) ) + "\"" ) ) ; } finally { try { br . close ( ) ; } catch ( Exception e ) { System . out . println ( "Debug.loadConfigFile():<seq2seq4repair_space>error<seq2seq4repair_space>while<seq2seq4repair_space>closing<seq2seq4repair_space>br" ) ; } } } } private static void writeLog ( String string ) { } }

Fix:
Debug . ERR_LEN = Integer . parseInt ( line . substring ( 7 ) ) ;